Percutaneous catheters are inserted into the vascular system of a patient as part of numerous therapeutic and diagnostic procedures. For example, a percutaneous mechanical circulatory support device, also commonly referred to as a heart pump, can be introduced into the vascular system of a patient through the femoral artery and inserted into the heart (e.g., the left ventricle) to pump blood from the heart into a blood vessel (e.g., the aorta). This pumping action can assist the natural cardiac pump function or replace the natural cardiac pump function. Percutaneous catheters may also be used for other procedures such as angioplasty, electrophysiology study, and ablation.
It is often desirable to fix a percutaneous catheter at a particular location within a patient. In the more specific case of a heart pump, for example, it is desirable for the pump to remain fixed in place in a position that optimizes the flow of blood from the heart and into the blood vessel. If the heart pump strays too far in or out from this optimal position in the heart, reduced flow and/or other complications may arise. For example, when the pump is positioned too far in the left ventricle such that the inlet and the outlet port(s) are both within the ventricle, the device can cause blood to circulate within the left ventricle rather than being delivered into the ascending aorta, thereby decreasing the support provided to the patient. Additionally, if the outlet port(s) of the heart pump moves it may be blocked by leaflets of a valve (e.g., the aortic valve). Blood delivered by the heart pump may impinge on the valve, which can cause lysing of blood cells or hemolysis due to shear stress. When the device is in such a position, the valve may also interfere with the flow of blood through the device, decreasing the support provided to the patient.
It may be desirable for a percutaneous catheter to remain in a patient for a long period of time, such as for a patient who requires long-term assistance with cardiac pumping. However, when a percutaneous catheter remains in a patient for a long period of time, it can be more difficult to maintain the position of the percutaneous catheter in the patient. Movement of the patient can cause the percutaneous catheter to stray from its desired position. For percutaneous catheters that are inserted into the heart of a patient, the normal pulsatility of the heart can cause the catheter to stray from its desired position and this can require user intervention.
One solution for maintaining the position of a percutaneous catheter is to reduce slack in the catheter to reduce the possibility of movement. Another solution for maintaining the position of a percutaneous catheter inserted into the heart is a flexible atraumatic extension that extends from the distal end of the catheter. This extension may reduce the possibility of the percutaneous catheter slipping too far from its optimal position into the heart. However, other solutions would be desirable in addition to or instead of these mechanisms. Additionally, it may be desirable to fix the orientation of the catheter within the body of the patient to optimize system performance.